Float assembly



E. F. BRILL FLOAT ASSEMBLY Jan. 15, 1963 BY W E. F. BRILL FLOAT ASSEMBLY Jan. 15, 1963 5 Sheets-Sheet 2 Filed July 8, 1958 Mm MW Q wTl' Jan. 15, 1963 E. F. BRILL 3,073,271

FLOAT ASSEMBLY Filed July 8, 1958 v 5 Sheets-Sheet 3 INVENTOR.

5' award 5/2 41 Jan. 15, 1963 E. F. BRILL 3,073,271

FLOAT ASSEMBLY Filed July 8, 1958 5 Sheets-Sheet 4 INVENTOR.

Jan. 15, 1963 Filed July 8, 1958 E. F. BRILL FLOAT ASSEMBLY 5 Sheets-Sheet 5 United States Patent Filed July 8, 1958, Ser. No. 747,221 8 Claims. {CL 114-.5)

This invention relates to buoyant structures and more particularly to buoyant structures of modular form and mechanism for joining sameinto various combinations, particularly, for forming floating piers and-for other uses.

While the invention has been shown and will be described herein, particularly in connection with a floating pier, or the like, it is to be understood that certain broader aspects of the invention are not to be limited to such use, but may be employed for all similar purposes, for example, for floating piers of other forms and for floating docks, diving rafts, floats and the like, of unitary or sectional form, and for numerous other purposes.

While the sections are particularly advantageous for their buoyant characteristics and for the purposes set forth, it is to be understood that they may be used as an inexpensive bridge for spanning open dry ditches of limited length. Possibly two or three sections totaling 16 to 24 feet may be used by the military to permit men to walk over the surfaces of the sections. The sections, while of the character described, would not be immersed in water in such case. A bridge composed, for example of three sections would weigh approximately 300 pounds, which is light enough to be handled by two men.

In buoyant structures of the character with which the present invention is concerned it is desirable that the walls of such structures will not be deleteriously affected by fresh or salt water, or hot sun, or freezing temperatures, and will not leak, waterlog, rust, corrode, mildew or rot and will be gasoline, oil and alcohol proof.

It is also desirable that the buoyant units of the floating pier, or other structure, be stabilized against generally horizontal and vertical movements, particularly under thrusts-imposed thereon, and that the sections, and the structure formed by joining the sections together,-have distributed support over substantially the entire area thereof in use.

'It is further desirable that the buoyant sections be capable of being joined in different relations, depending upon the desired configuration of the assembled structure; that the connections between the sections be not diflicult to make or difficult to release; and that the connections act rigidly to connect the sections adjacent their top and bottom surfaces, or along their upper and lowermargins.

According to the present invention the buoyant unit or section comprises a top structure of buoyant character presenting an upper surface, and a substantially rigid walled vessel secured to the top structure in position beneath the same; the underlying vessel having permanently open and restricted, or limited, water filling ports, and restricted, or limitedsize air vent ports, or otherwise permanently open, to permit complete filling of the vessel with water to. stabilize the buoyant structure against generally horizontal and vertical movements, and, at the same time, to present distributed support on the water over substantially the entire bottom area of the upper buoyant structure.

Another feature of the invention resides in providing an upper buoyant part in the form of a shell molded or otherwise formed from material in the plastic and fiber 3,073,271 Patented J an. 15,, 19.63

Another feature resides in the provision of buoyant sections of modular design for adaptability and-interchangeability of the sections, or units and accessories, and which will permit joining the sections in numerous different relations, depending upon the desired configuration of the assembled floating pier or other structure.

Another feature resides in the provision of an improved 7 form of mechanism for rigidly joining the buoyant sections adjacent to their top and bottom surfaces, or along their upper and lower margins and which will provide an assembled structure in which the strength of the structure with respect to the various loads and forces which are imposed is greatly augmented; also a joining mechanism, which, when in place, will release at least certain of the walls of the outer shells of the buoyant units of the loads and forces imposed on the assembled structure.

Another feature resides in the provision of an improved form of joining mechanism for connecting and releasing the units without difiiculty, and more particularly a mechanism which will enable conveniently establishing connection of the units along their upper margins, and automatically establishing the connections between the lower margins of the units, after the connections between the upper margins of the units have been established.

Another featureresides in the provision ofjoining members which are reversible so that only one type joining member need be manufactured. With these members reversed they may be joined to join adjacent units together.

Another feature resides in increasing the thickness of the reinforced plastic shell, for example, at the corners and places along the sides and in joining the sections at the places of increased thickness of the shell, for example, by sheet metal screws, or the like.

Another feature resides in the provision of molded-in gussets' or load distributing plates for transferring pintle loads to the reinforced plastic or other shell of the buoyant units and vice versa.

Another feature resides in the provision of heating and cooling grooves for forming and solidifying, Within the outer shell, for example, polystyrene material in head form into rigid shape to permit rapid molding by requiring less total time in the molding operation.

Another feature resides in the provision of cover plates to cover joints and corner gusset plates to add mechanical strength.

Another feature resides in the provision of a rod arrangement embedded in the reinforced plastic, or other shells of the buoyant units to which pintles are fastened for joining the units together;

Another feature resides in the provision of corrugated top and bottom surfaces to give mechanical strength and to distribute local or concentrated loads which will permit use of a thin bottom and/ or top deck surface.

Further objects and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings, it being understood that the invention is limited only within the scope of the appended claims and not to the particular showing the upper horizontal structure joined to the undermembers which are fastened to the adjacent ends of ad jacent units and the connecting mechanism between these members; p j I FIGURE. 7 is a fragmentary perspective view of one 'of the connector members shown in FIGURE 6;

FIGURE 8 is a perspective view of the spring latch shown partially in FIGURE 6;

FIGURE 9 is a detail section taken on the-line 9-9 of FIGURE 4 to show one of the molded-in side inserts;

FIGURE 10 is a more or less diagrammatic top plan view showing one illustrative form of floating pier according to the present invention;

, FIGURE 11 is a fragmentary detailed section taken on the line 11-'1l of FIGURE 10 and showing one of the joint cover plates in section;

FIGURE 12 is a detail section taken on the line 12-12 of FIGURE 2;

FIGURE 13 is a sectional view similar to FIGURE 2 butshowing the polystyrene material bonded to the interior of theshell of the buoyant unit of ribbed instead of v solid form; v

FIGURE 14 is 'a'fragnientary sectional view showing a moldedin corner insert instead of connecting rods as in FIGURES 1 and 2.

FIGURE 15 is end view of another form of joining or connecting member; I

FIGURE 16 is a side view of the member shown in FIGURE 15; and

FIGURE 17 is a fragmentary sectional view showing a pair of members like the one shown in FIGURES 15 and 16 reversed and joined by a pin.

Referring now to the drawings, the buoyant unit as shown-particularly in FIGURES 1, 2 and 4 inclusive,

comprises an upper part 1 of buoyant character presenting an upper load bearing surface 2, and a substantially rigid vessel 3 secured to the upper part 1 (FIGURE 4) beneath the same and having an open top 5 presented to the bottom of the upper part 1 over substantially its entire area.

. The upper buoyant part 1 preferably comprises a first outer shell6 molded of resin material, for example from the group consisting of phenolic, nylon, melamine, alkyd, polyester, polystyrene, and silicone resins and reinforced with fibrous glass, such, for example, as Fiberglas, marketed by" Owens-Corning Fiberglas Corporation of New York, New York. The upper surface of the shell 6 is preferably corrugated at 7 to give mechanical strength and to distribute local or concentrated loads. This permits the use of a thin top deck surface; The shell 6 is of box-like form having a top wall, two side walls 8, two end walls 9 and open at the bottom. The lower ends of the 'Walls 8 and 9 are shown flanged outwardly at 10.

The plastic shell 6 has, for example, internal integral "and longitudinally extending enlargements 11 in which rods 12 are embedded and molded in place. The rods 12 are disposed atfthe opposite longitudinal corners of the shell 6, in proximity to the upper margin of the shell and extend parallel with the side walls 8, 8 and from end-toend of the shell. The rods 12 are preferably formed, for example, of stainless steel, brass, or bronze, although they may be Many other suitable material, preferably, which are exposed externally at the ends 9 of the shell andthe threaded openings 15 are externally exposed at the sides 8 of the shell for joining the buoyant structure to a similar structure as will hereinafter appear.

Centrally between the opposite ends 9 of the shell a metal insert 16 is embedded and molded into place in the plastic material of each: of the side walls of the shell and in proximity toeach upper corner of the shell. As shown in FIGURES 4 and 9 the inserts 16 are of angular form, each having an upright leg 17 embedded and molded in place in the adjacent side wall 8 and a leg 18 molded in place in the top wall of-the shell 6; The legs 17 and18 have openings 20 through which the plastic material extends to bond the insert 1 6 firmly in place. Each leg 17 has a pair of integral enlargements 21 molded in place in the plastic material. The enlargements 21 have openings, tapped, or internally threaded 22.1 The threaded openings 22 are externally exposed at the opposite sides of the shell 6.

To provide a modular design of buoyant unit for adaptability and interchangeability of sections and accessories, the transverse distances between the axes of the threaded openings 14 are preferably the same as the distances between the axes of the threaded openings '15 at one end of the shell and the nearest threaded openings 22 along the central portions of the sides of the shell, and the distances between the other threaded openings 22 and the threaded openings 15 at the other end of the shell are also preferably the same. This permits the units to be joined in side-by-side, and end-to-end relation, as will hereinafter appear.

' One suitable form of buoyant unit may be of an overall length of about 92 inches and an overall width of 44 inches with the threaded openings 14 positioned 42 inches apart and the openings 15 spaced 42 inches from the related openings 22. This, of course, is merely illustrative and it is to be understood that the shapes and configurations of the buoyant units may vary within the broader aspects, of the invention. With the dimensions above set forth the openings 22 may be spaced, for example, 6 inches apart.

In FIGURES 2 and 4 the inside of the shell 6 is shown filled at 24 with a plastic substance bonded to the inner surfaces of the side walls 8, end walls 9 and top wall 19.

One suitable filling 24 is formed by placing within the interior ofthe shell 6 polystyrene beads that can be expanded to about 40 times their volume to fill the shell with a thus foamed material, and further expanding and knitting the beads together with heat. The beads or cells may, for example, be Styrofoam plastic beads or cells as marketed by The Dow Chemical Company of Midland, Michigan.

After the beads or cells are placed in the shell 6 the formation of the filling may be accomplished by applying over the open bottom of the shell a plate 25 having apertures 26, as shown, more or less diagrammatically, in FIGURE 2. An adhesive, such as EC-524, EC-880, EC24, EC-260 or epoxide adhesive Bondmaster M664, mentioned by the aforementioned The Dow Chemical Company in its literature; also .by Minnesota Mining and Mfg. Co. in its literature, is preferably applied to the inner surfaces of the side walls 8, end walls 9 and top wall 19 before expanding the plastic beads.

It is contemplated within the scope of the broader aspects of the present invention to use other foam forming materials, for example, a urethane foam material, such as Selectrofoam 6004, a polyester resin, or Selectrofoam 6005, a prepolyrner. These materials are marketed by Pittsburgh Plate Glass Company of Pittsburgh,

Pennsylvania. Such materials will bond directly to the Fiberglas shell without additional adhesive.

Steam is then injected through the apertures 26 further to expand and knit the plastic beads together, completely to fill the shell 6 and to adhere or bond the plastic filling to the inner surfaces of the walls of the shell. The resulting filling has an extremely low denama-m1 sity. -It possesses good thermal insulating properties; does not absorb water even after long periods of in1- mersion and it has high resistance to rot, mold growth and decay. It is only about ,4 as heavyas polystyrene, and is 30% more buoyantthan cork. Moreover, it possesses good structural strength, and requires no special handling to prevent damage.

As the expanded polystyrene material cools or solidifies, the surfaces are subjected to a greater rate of heat abstraction than the center of the filling. This. provides high compressive strength alongthe top surface of the shell6 and permits the plastic shell to be very thin, i.e. about 7 of an inch to about 9 of'an inch. The plastic shell of thecharacter described may be colored as desired and will retain its color after use. It will not leak, waterlog, rot, mildew,'rust or corrode, and is worm proof, weather proof, gasoline, oil and alcohol proof. Salt nor fresh water nor hot sun or freezing temperatureswill affect it.

If desired, the plate 25 may be provided with prongs 30, as shown, in FIGURE 2 so' that upon completion of the filling, grooves 31 will be provided therein as shown in FIGURE 4. These grooves 31 may serve as heating or cooling grooves for forming and solidifying the plastic filling material into rigid shape. This permits rapidmolding by requiring less total time in molding.

Instead of expanding the plastic material within the shell, the, reinforced plastic material may be applied in the form of boards or pieces as shown, for example, in FIGURE 5.

In FIGURE 5 the shell 6 may be similar to the shell 6 previously described. Boards or pieces 32, 33 and 34 of polystyrene plastic material, or other suitable material are applied and cemented to the inner surfaces of the top wall 19', side walls 8' and end walls 9 completely to line the interior of the shell. A plurality of partition members 35 of similar polystyrene material are cemented or bonded along their margins to the. pieces 32 and 33. A board or piece 36 of similar material may be applied over the bottom margins of the pieces 32, 33, 34 and 35 and cemented or bonded thereto, thus forming a plurality of closed 'and sealed voids 37 within the shell 6. This construction imparts strength alongthe upper load bearing surface and imparts rigidity to the structure.

The rods or connecting members 12' as shown in FIGURE 5. may be similar to the rods or connecting members 12 as previously described.

Upon completion of the application of the polystyrene, or other suitable material to the interior of the shell 6 a rigid walled vessel 38 is secured. to the upper shell 6 in position beneath the same as shown in FIGURE 4.

The vessel 38 may comprise a shell molded of resin material precisely like the shell 6 except for theprovision of restricted water inlet ports and air vent openings in the walls thereof, as will be presently described.

The shell 38' is. of box-like form having a bottom wall 39 corresponding to the top wall of the upper shell 6 and sidewalls 40 and end walls 41 corresponding to the side walls and end walls of the shell 6. The shell 38 'is open at the top and the upper ends of the side and end walls have flanges 42 cemented, or joined to the flanges of the shell 6, or having engaging fit therewith, with the shell 38 inverted with respect to the shell 6. The bottom surface of the bottom wall 39 is preferably corrugated at 43 to provide mechanical strength and to distribute local or concentrated loads.

The connecting, rods 44 and the metal connection inserts 45 are similar to those previously described in connection with the upper shell and are embedded. and molded in the plastic material of the lower shell 38 precisely as described in connection with the corresponding parts 12 and 16 of the upper shell. The locations of the connecting rods and metal inserts are similar to those described in connection with the upper shell except. that the shell 38 being-inverted, the rods 44 and wall 39 in FIGURE 4 and by corresponding primed referencecharacters inFIGURE 5, and the upper ends'of the side and end walls 40 and 41 have a series of limited size air vent openings. 49. When the buoyant structure is. placed in water the bottom vessel is normally completely below the water level and the water inlet openings '48and air ventopenings 49 permit complete filling of the. vessel or shell- 38 with water. This stabilizes the buoyant structure against generally horizontal and vertical movement, or displacementin the water under thrusts imposed upon the buoyant structure in use.

At the same time thefilling of the vessel 38 with water up. to the bottom surface of the upper'buoyant part 1 provides distributed support of the upper buoyant part on the water over the entire bottom area of the upper part'when the structure is positioned for use in water. This is an important aspect of the invention. The openings inthe walls of the shell 38 also permit complete drainage of the water from the shell when the structure is withdrawn from the water.

It is contemplated within the scope of the broader aspects of the present invention to provide the. lower vessel or shell 38' with an opening or a plurality of openings only at the upperends of the vertical walls thereof to permit complete filling with water, without the bottom openings. This will necessitate tilting the structure to fill the lower vessel with'water and to empty the water from this vessel.

Releasable connections between the upper buoyant part and the underlying stabilizingpart are also contemplated, to permit the parts to be separated for handling, shipment-or transporting and joining of the parts, for example, at the place of use. In such case, the upper and lower parts may be dimensioned and proportioned to'permit one part to be-telescoped over the other part for greater compactness in handling, shipping or transporting the structure.

'For the purpose of.j0ining the buoyant structure, for example, end-to-endi to a similar buoyant structure, the opposite ends of the structure have, for example, connectingmernbers 50 and 51 applied thereto as shown in FIGURES 4, 6, 7 and 8.

The connecting member 50, for example at the left hand end of the unit, asshown in FIGURE 4, comprises a vertically elongated 'bar 52 apertured' at 53 near its upper and lower ends to receive the shanks of bolts or screws 54 which when screwed into the openings 14 firmly secure the upper and lower ends of the bar 52 to the adjacent exposed ends of the rods 12 and 44 and against the adjacent end of thebuoyant unit. The other connecting'member 51 comprises a similarly vertically elongated bar 56 apertured at 57 near its upper and lower ends to receive the shanks of bolts or screws 58 which, when screwed into the openings 14 at the opposite ends of the rods 12 and 44 firmly secure the upper and lower ends of the bar .56 to the opposite exposed ends of the rods' 12 and-'44 andagainst the opposite end of the buoyant unit.

Itis contemplated, within the scope of the broader aspects of the invention, to. join the unitsotherwise than with through rods and connecting bars, or metal inserts.

For-example, the "corners and places along the sides of the reinforced plastic shell, or shells, may be thickened and the units may be joined bysheet metal screws, or other connecting means cooperating with, or engaging the thickened portions of the shell.

The bar 52 has a pair of spaced arms 60 near its upper end and a similar pair of spaced'arms 60 near its lower end. The bar 56 has a pair of spaced arms 62 near its upper end and a similar pair of spaced arms 62 near its in FIGURE 6.

' coil spring 66 is provided adjacent each arm 65. and acts yieldingly to. turn :thearm about the pintle 64 i.e. in a clockwise direction for the upper latch arm 65 as shown The spring 66 is shown looped at 67 about the pintle 64 in FIGURE 8 and has one end 68 for abutting, forexample, a shoulder 69 on thebar 56. A suitable stop 70 may, if desired, be provided for. limiting'turningmovement of the latch arm about the pintle 6-4.

Each pair of arms 60 carries a transverse horizontal pint1e 72 which projects through the space between the arms 60 and outwardly at its ends beyond the" outer sides of the arms 60. The arms 62have slots 74 opening from the ends thereof for receiving the projecting end of the pintle 72.

The inner margins of the bars 52 and 56 may be arched as shown at 76 in FIGURE 4 to clear the joined flanges 10 and 42 of the joined shells 6 and 38,

With the bars 52 and 56 and connecting means in place on the opposite ends of the buoyant unit this unit is joined end-to-end to a similar unit by placing the units end-to-end with the arms 62 on the end of one unit' straddling the arms 64 on the adjacent end of the other unit. By placing the upper arms 60 at the top of one unit 'betweenthe arms 62 on the adjacent endof'the other .unit the'latch' arm 65 will snap' downbetween the arms 60 and into engagement with the pintle 72' Thereupon,

upon bringing the adjacent units into coplanar relation, the arms69 at the bottom of one unit will move to position between the arm .62 on the adjacent end .ofthe other unit and the lower latch arm 65 will snap auto matically into engagement with the lower pintle 72.

The connecting means for automatically effecting the connection at the lower portions of the units after the connection at the top margins has once been established makes it possible to connect the units without getting into the water.

present invention.

Instead of employing a spring latch connecting mechanism as described in connection with FIGURES 4, 6, 7 and 8, connecting bars of the form shown in FIGURES l5, l6 and 17' may be employed.

The vertically elongated connecting bar, shown at 115 in FIGURES 15, 16 and 17, is apertured at its upper and lower ends atllfi to receive, for example, the shanks of bolts or screws for securing such bars to the buoyant and stabilized units.

I tongues 117. Pins or posts 124 are inserte through the registering apertures 121 and 122'and join the. buoyant and stabilizedunits together. Thus, only one type of joining or connected bar need be manufactured and the units are joined'with ease and facility.

It is contemplated to make the tongue 113 separate from the bar Y115 and to fasten the same to the bar for sidewise adjustment for thepurpose of assuring sidewise alignment of connected'unitsg Side-by-side or end-to-side connection of the units is accomplished by fastening bars corresponding to the bars 52 and 56 to the desired sides of the units by bolts screwed into the desired side openings 15 and/ or 22. The bars being provided with pintles and latch arms may then be connected as described for the end connections.

With the connecting or joining mechanism as shown and described, the buoyant units are rigidly joined together adjacent to their top and bottom surfaces, or along their upper and lower margins. This provides an assembled structure in which the strength of the structure with respect to the various loads and forces which are imposed is greatly augmented. The joining mechanism, when in place, releases the walls of the shells 6 and 38 of much of the loads and forces imposed on the assembled structure, and the connections may be established conveniently and expeditiously.

In FIGURE 13 the polystyrene plastic material is similar to that shown in FIGURES 2 and 4 but instead of being substantially solid with grooves therein it has spaced ribs 80 molded integral with the'balls 81 and 82 and provided with air spaces 85 therebetween and with a watertight sheet 83 of polystyrene plastic or other suitable mate- This is another important feature of the rial cemented over the bottom ends of the ribs 80 and walls 82 and 84m seal the air pockets 85;

Within certain aspects of the invention, omission of the sheet 83 from the bottom of the unit shown fragmen.

tarily in FIGURE 13- is contemplated. In use, Water will then rise a few inches in the spaces 85. Any tendency of the water level to drop in the spaces, will, in effect, produce a vacuum, which will tend to hold the water in the spaces 85. Due to size a very substantial holding down effect will be produced and better stability will result.

The bar 115 has apair of integral spaced projecting Y I the bars 52 and 56 they are appliedin reversed relation,

i.e. with the. tongues 117 of one bar near the top of one unit and with the tongues117 of the other bar near the bottom of they other unit.

The units are then placedend-to-end with the tongue 118 near thetop of one unit fitting between the tongues 117 of the other unit and with the tongue .118 near the bottom of the other unit fitting between tongues. 117 near the bottom of the first unit. The inner sides of the tongues 117 are preferably tapered at 119 and the outer sides of the tongues 118 are correspondingly tapered at 120 to facilitate free entry of the tongues 118 between the tongues 117 and to provide snug fit when in position. This tapering of the tongues may be similarly embodied in the arms and 62 shown in FIGURl-ES 4, ,6 and 7.

The tongues 117 have apertures 121 and the tongues 1-18 have apertures 122 which register with the apertures 121 when tongues 11% are in position fitting between the The illustrative floating pier shown in FIGURE 10 comprises a buoyant section 1 and similar buoyant sections 1a, 1b, and 10 connected along their upper and lower margins and end-to-end as previously described. A buoyant section 142 is connected to the section 10 in side-by-side relation and a buoyant section lie is connected to a section 1d in end-to-side relation, whereas a further.

buoyant section 1 is connected to the section 1e in sideby-side relation.

Cover plates 36, 87 and 88 may be applied to cover the joints between the respective sections. These cover plates are preferably formed of reinforced plastic material as described'for the shells 6 and 38 and have down turned marginal flanges 941? as shown in section in FIGURE 11. These cover plates may be clamped in place by the joining together of adjacent buoyant sections or units. For example, the flanges may extend down between the bars 52 and 56 and the adjacent vertical surfaces of the buoyant units and have apertures through which the shanks of the screws or bolts 54 and 58 may pass to secure the cover plates in place. The cover plate 86 is shown as of the same length as the buoyant units and the cover plate 87 is shown of a length equal to the width of the modular units.

The connection between units 1 and la at the position of the cover plate 87 may be a hinge or pivotal connection, permitting the connected units outwardly of this position to have hinge or pivotal movement vertically as a unit about, for example, the connection between the sections 1 and 1a. 1

In FIGURE 10 the ground or shore line is indicated at 91 and the water is indicated at 92. The inner or shore end of the unit 1 may be anchored to the ground by a stake 93 passing through a metal plate 93' on the inner end of the unit 1. Another stake 94 passing, for example, through another metal plate 95 on the end of the unit 11 may be used to anchor the floating pier out in the water.

A corner gusset plate 98 may be applied as shown in FIGURE or otherwise as desired to add mechanical strength. These gusset plates 98 may be formed of reinforced plastic material as described for the shells 6 and 38 and have downturned flange-s 99 as shown in dotted lines. The flanges 99 are apertured for attachment of the adajcent side flanges of the gusset plates to the rods or metal inserts of the buoyant units by screws 10.0. The

diagonal side of the gusset plate is also preferably flanged and a leg 106, embedded in what is to constitute the top.

wall 107 or the bottom wall of the shell. The brackets 102 are similar to the inserts or brackets 16 shown in FIGURE 4 but are disposed at the ends in lieu of the connecting rods. i i

'The legs 103 and 106 have openings 108v through which the plastic material extends to bond the brackets firmly in place. Each leg may have an integral enlargement 109 molded in place in the plas tic material. These enlargements have openings tapped or int ernally threaded at 110 to receive the screws 54 and 58 as previously de-.

scribed for attaching the bars 52 and 56 to the ends and sides of the units in proximity to the upper and lower margins thereof.

The bars 52 and 56 and related parts as shown in FIG- URES 6, 7 and 8 may be formed of stainless steel, brass, I

bronze or other suitable metal which will not rust or corrode and at least the exposed portions of the other metal parts may be formedof metal which is corrosion and rust proof.

It is contemplated toso proportion the weight of the water in the stabilizing chamberwith respect to the buoyancy. of the upper buoyant part so that little or substantially no up and down movement of the structure will occur as the result of. waves in'the water. If the structure were weightless this may be accomplished by making the buoyant volume equal to the water containment vvlumes? the unithas we g inwater the u y volume is increased to compensate for the weight of the unit or substantially to compensate for the weight of the unit in water and allowing for the water that passes through the openings.

The embodiments of the invention shown in the drawings are for illustrative purposes only and it is to be especially understood that said drawings and the accompanying specification are not to be construed as a definition of the limits or scope of the invention, reference being had to the appended claims for that purpose.

I claim:

1. A buoyant structure comprising an upper part of buoyant character presenting an upper load bearing surface, and a substantially rigid walled vessel secured to said upper part in position beneath the same and having an open top presented to the bottom of said upper part over substantially its entire area, the walls of said vessel having permanently open and relatively restricted water inlet ports and air vent openings permitting complete filling of said vessel with water tostabilize said structure against generally horizontal and vertical movements and to provide distributed support of said upper buoyant part on the water over substantially the entire bottom area of said upper part when said structure is positioned for use in Water n Pe mit n omplete ra n e o h Water f o aid vesse when the s ructurei Withdrawn from the water, wherein the upper buoyant part comprises a shell. of reinforced plastic material containing t r y h re f a foa d mater a s pp rtin the up- P r l b a n urface and imuart s isi ity to th structure.

2. A buoyant structure comprising an upper part of bu ya harac pre enti g n pper oad be rin a n a u s a y r id wa edvesse secur to said upper part in position beneath the same andhaving an open top presented to the bottom of said'upper part over substantially its entire area, the. walls of said vessel having permanently open and relatively restricted Water inlet ports, and air vent openings permitting complete filling ofsaid vessel with water to stabilize saidflstructure against generally horizontaland vertical movements and to provide distributed support ofsaid upperbuoyant part on the water over substantially the entire bottom area i buoyant character presenting an upper loadbearing surface, and a-substantially rigid walled vessel secured to said upper part in position beneath the. same. andhavingan open top presented to the bottom, of said upper part over substantially its entire area, the Walls of said vessel hay- I ing permanently open and relatively restricted water inlet ports and air vent'openings permitting completefilling of said vessel with water to stabilizesaid structure against generally horizontal and vertical movements andto. provide distributedsupport of said upper buoyant part on the water over substantially the entire bottom area of said upper part when said structureis positioned for. use in water and permitting completedrainage ofv the water from said vessel when the structure is withdrawn from the water, wherein the upper buoyant part comprises a shell of reinforced plastic material and" pieces of polystyreneplastic material adhered. to. the inner surfaces of the W lls of sa d shellv nd o. a th r to form-t P ity of closed voids within said shell.

4., A buoyant structure comprising an .upper part of buoyant character presenting an, upper load bearingsurface, and a substantially rigid; walled vessel secured to said upper part in position beneath the same and having an open top presented to the bottom of said upper part over substantially its entire area, the walls of said vessel having permanently open and relatively restricted water inlet ports and air vent openings permitting complete ,filling of said vessel with water to stabilize said structure against generally horizontal and vertical movements and to provide distributed support of said upper buoyant part on the water over substantialy the entire bottom area of said upper part when said structure is positioned for use in water and permitting complete drainage of the Water from said vessel when the structure is withdrawn from the water, wherein the upper buoyant part comprises a said upper part in position beneath the same and having an open top "presented'to the bottom of said upper part over substa'ntially its entire area, the walls of said vessel having permanently open and relatively restricted water inlet ports and air'vent openings permitting complete filling of said vessel'withwater to stabilize said structure against generally horizontal and vertical move- 1 mentsand to provide distributed support of said upper buoyant partion the water over substantially the entire bottom area of said upper part when said structure is positioned for use in water and permitting complete drainage of the water from said vessel when the structure is withdrawn from the water, wherein the upper buoyant part comprises a first shell of reinforced plastic material 1 open at the. bottom and having a top wall forming the v upper load bearing surface, said first shell containing a polystyrene plastic material supporting the upper load K bearing surface and imparting rigidity to the structure, said vessel comprising a second shell of reinforced plastic material and having an open top joined to the open botftom of said first shell, and connecting means molded in place insaid upper and lower shells for rigidly joining said buoyant structure to a similar structure along the upper and'lower margins thereof.

6. A buoyant structure comprising an upper part of buoyant character'presenting an upper load bearing surface, and a substantially rigid walled vessel secured to inletports and air vent openings permitting complete filling of said vessel with water to stabilize said structure against generally horizontal and vertical movements and to provide distributedsupport of said upper buoyant part on the water, over substantially the entire bottom area .of

, said upper part when said structure is positioned for use inwaterand permitting complete drainage of the water from said vessel when the structure is-withdrawn from the water,-wherein there are connecting rods disposed within and extending throughout one horizontal extent of the structure and in proximity to the upper and lower margins of the structure, the opposite ends of said rods being exposed at opposite margins of the structure for joining said buoyant structure to a similar structure along the upper and lower margins thereof.

7. A buoyant structure comprising an upper part of buoyant character presenting an upper load bearing surface, and a substantiallyrigid walled vessel secured to said upper part in position beneath the same and having an open top presented to the bottom of said upper part over substantially its entire area, the walls of said vessel having permanently open and relatively restricted water inlet ports, and air vent openings permitting complete filling of said vessel with water to stabilize said structure against generally horizontal and vertical movements and to provide distributed support of said upper buoyant part on the water over substantially the entire bottom area of said upper part when said structure is positioned for use in water and permitting complete drainage of the water from said vessel when the structure is withdrawn from the water, wherein there are pin connections on the end of the buoyant structure for joining said buoyant structure to a similar structure along 7 the upper and lower margins thereof.

8. A buoyant structure comprising an upper part of buoyant character presenting an upper load bearing surface, and a substantially rigid walled vessel secured to said upper part in position beneath tie same and having an open top presented to the bottom of said upper part over substantially its entire area, the walls of said vessel having permanently open and relatively restricted water inlet ports and air vent openings permitting complete filling of said vesselwith water to stabilize said structure against generally horizontal and vertical movements and to provide distributed support of said upper buoyant part onthe water over substantially the entire bottom area of said upper part when said structure is positioned for use in Water and permitting complete drainage of the water from said vessel when the structure is withdrawn from the water, wherein there are pintles on the ends of said buoyant structure, and spring latch members on said pintles for engagement with other pintles for joining said buoyant structure to a similar'structure along the upj per and lower margins thereof.

References Cited in the file of this patent UNlTED STATES PATENTS 2,271,058 Binns Jan. 27, 1942 2,408,871 Nelson Oct. 8, 1946 2,430,178 Kurfiss Nov. 4, 1947 2,653,139 Sterling -1 Sept. 22, 1953 2,660,194 Hoffman Nov. 24, 1953 2,727,278 Thompson Dec. 20,1955 2,742,012 Bridges Apr. 17, 1956 2,857,872 Usab' Oct. 28, 1958 2,858,790 Russell Nov. 4, 1958 2,876,726 Robeshaw Mar. 10, 1959 2,879,735 Pointer Mar. 31, 1959 2,892,433 Walker June 30, 1959 FOREIGN PATENTS 800,370 Great Britain Aug. 27, 1958 

1. A BUOYANT STRUCTURE COMPRISING AN UPPER PART OF BUOYANT CHARACTER PRESENTING AN UPPER LOAD BEARING SURFACE, AND A SUBSTANTIALLY RIGID WALLED VESSEL SECURED TO SAID UPPER PART IN POSITION BENEATH THE SAME AND HAVING AN OPEN TOP PRESENTED TO THE BOTTOM OF SAID UPPER PART OVER SUBSTANTIALLY ITS ENTIRE AREA, THE WALLS OF SAID VESSEL HAVING PERMANENTLY OPEN AND RELATIVELY RESTRICTED WATER INLET PORTS AND AIR VENT OPENINGS PERMITTING COMPLETE FILLING OF SAID VESSEL WITH WATER TO STABILIZE SAID STRUCTURE AGAINST GENERALLY HORIZONTAL AND VERTICAL MOVEMENTS AND TO PROVIDE DISTRIBUTED SUPPORT OF SAID UPPER BUOYANT PART ON THE WATER OVER SUBSTANTIALLY THE ENTIRE BOTTOM AREA OF SAID UPPER PART WHEN SAID STRUCTURE IS POSITIONED FOR USE IN WATER AND PERMITTING COMPLETE DRAINAGE OF THE WATER FROM SAID VESSEL WHEN THE STRUCTURE IS WITHDRAWN FROM THE WATER, WHEREIN THE UPPER BUOYANT PART COMPRISES A SHELL OF REINFORCED PLASTIC MATERIAL CONTAINING INTERNALLY THEREOF A FOAMED MATERIAL SUPPORTING THE UPPER LOAD BEARING SURFACE AND IMPARTING RIGIDITY TO THE STRUCTURE. 